• YAKHAK HOEJI
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• v.47 no.4
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• pp.218-223
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• 2003

Effect of taurine treatment on metabolism of glutathione (GSH) was studied in adult male ICR mice. An acute injection of taurine (250 mg/kg, ip) resulted in a significant decline of hepatic GSH level at t = 6 hr, but plasma GSH level was not altered. The activity of GSH-related enzyme in liver, such as GSH peroxidase, GSSG reductase, GSH S-transferases, ${\gamma}$-glutamylcysteine synthetase or ${\gamma}$-glutamyltranspeptidase, was not affected by taurine at t = 2.5 or 6 hr. Plasma cysteine and cystine levels were elevated rapidly following taurine treatment. Hepatic cysteine level was decreased by taurine, reaching a level approximately 70％ of control at t = 4 and 6 hr. In conclusion, the results indicate that an acute dose of taurine decreases hepatic GSH level by reducing the availability of cysteine, an essential substrate for synthesis of this tripeptide in liver. It is also suggested that taurine may decrease the cysteine uptake by competing with this S-amino acid for a non-specific amino acid transporter.

• YAKHAK HOEJI
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• v.39 no.6
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• pp.654-660
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• 1995

The present study was attempted to investigate the mechanism of oxidative cellular injuries which occur in diabetic rats by determining changes of antioxidant enzymes activity in the lung of alloxan-induced diabetic rats, the contents of glutathione in the lung, liver, blood samples, and ${\gamma}$-glutamylcysteine synthetase activities in the liver. Superoxide dismutase activities (SOD), including Cu, Zn-SOD and Mn-SOD, decreased in the lung of diabetic rats compared with those of normal control rats. However, activities of catalase and glutathione peroxidase(GPX) activities were not affected in the lung of diabetic rats. In diabetic rats, glutathione contents in the lung, liver, and blood samples, as well as the activities of ${\gamma}$-glutamylcysteine synthetase in the livers which is known to be the key enzyme of glutatione biosynthesis, decreased significantly. From these experimental results, it is thought that the decrease in SOD activities in the lung, glutathione contents and ${\gamma}$-glutamylcysteine synthetase activities in some tissues in alloxan-induced diabetic rats may be the crucial cause of vullnerability to oxidative cellular injuries.

• YAKHAK HOEJI
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• v.49 no.1
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• pp.97-102
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• 2005

The protective effect of Yangguksanwha-tang (YST) against hypoxia-reperfusion insult was investigated in PC12 cells. To elucidate the mechanism of the protective effect of YST, cell viability, the changes in activities of superoxide dismutase, glutathione peroxidase, catalase, caspase 3 and the production of malondialdehyde were observed after treating PC12 cells with YST which was metabolized by rat liver homogenate. Pretreatment of YST with liver homogenate appeared to increase its protective effect against hypoxia-reperfusion insult. The result showed that YST had the highest protective effect against hypoxia/reperfusion at the dose of $2\;{\mu}g/ml$ in PC12 cells, probably by recovering the redox enzyme activities and MDA to control level.

• Nutrition Research and Practice
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• v.2 no.4
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• pp.195-199
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• 2008

Alcoholism has been associated with folate deficiency in humans and laboratory animals. Previous study showed that ethanol feeding reduces the dehydrogenase and hydrolase activity of 10-formyltetrahydrofolate dehydrogenase (FDH) in rat liver. Hepatic ethanol metabolism generates acetaldehyde and acetate. The mechanisms by which ethanol and its metabolites produce toxicity within the liver cells are unknown. We purified FDH from rat liver and investigated the effect of ethanol, acetaldehyde and acetate on the enzyme in vitro. Hepatic FDH activity was not reduced by ethanol or acetate directly. However, acetaldehyde was observed to reduce the dehydrogenase activity of FDH in a dose- and time-dependent manner with an apparent $IC_{50}$ of 4 mM, while the hydrolase activity of FDH was not affected by acetaldehyde in vitro. These results suggest that the inhibition of hepatic FDH dehydrogenase activity induced by acetadehyde may play a role in ethanol toxicity.

• Journal of Dental Anesthesia and Pain Medicine
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• v.22 no.6
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• pp.451-455
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• 2022

Glycogen storage disease (GSD) is a group of inherited disorders, which result in the deficiency of enzymes involved in glycogen metabolism, leading to an accumulation of glycogen in various organs. Deficiency of amylo-1-6-glicosidase (debranching enzyme) causes glycogen storage disease type III (GSD III). The main problems that anesthesiologists face in patients with GSD III include hypoglycemia, muscle weakness, delayed awakening due to abnormal liver function, possible difficulty in airway, and cardiomyopathy. In the face of these difficulties, airway preparation and appropriate glucose monitoring and support during the fasting period are important. The doses of the drugs to be used should be calculated considering the increased volume of distribution and decreased metabolic activity of the liver. We present the case of a child with GSD IIIa who underwent dental prosedation under general anesthesia. She was also being prepared for liver transplantation. This case was additionally complicated by the patient's serious allergic reaction to eggs and milk.

• Proceedings of the Korean Nutrition Society Conference
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• 2002.05a
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• pp.165-165
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• 2002

• Proceedings of the Korea Society of Environmental Biology Conference
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• 2004.12a
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• pp.104-104
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• 2004

• Bulletin of the Korean Chemical Society
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• v.11 no.6
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• pp.472-473
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• 1990

• 한국생물공학회:학술대회논문집
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• 2003.04a
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• pp.736-738
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• 2003

Ornithine decarboxylase (ODC) is the key enzyme in the synthetic pathway of polyamines. This enzyme is a homodimeric and a pyridoxal 5-phosphate (PLP) dependent enzyme. We have isolated, a cDNA clone encoding ODC from brain cDNA library constructed from flounder (Paralichthys olivaceus). The ODC cDNA contained a complete ORF consisting of 460 amino acids and one stop codon with comparison to nucleotide sequences of the flounder, zebrafish and rat ODC genes, the ODC genes were highly conserved. The transcription of ODC was analyzed with reverse transcription-polymerase chain reaction (RT-PCR) species in brain, kidney, liver, and embryo.

• BMB Reports
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• v.50 no.7
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• pp.367-372
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• 2017

Monoacylglycerol acyltransferase 1 (MGAT) is a microsomal enzyme that catalyzes the synthesis of diacylglycerol (DAG) and triacylglycerol (TAG). However, the subcellular localization and catalytic function domain of this enzyme is poorly understood. In this report, we identified that murine MGAT1 localizes to the endoplasmic reticulum (ER) under normal conditions, whereas MGAT1 co-localize to the lipid droplets (LD) under conditions of enriching fatty acids, contributing to TAG synthesis and LD expansion. For the enzyme activity, both the N-terminal transmembrane domain and catalytic HPHG motif are required. We also show that the transmembrane domain of MGAT1 consists of two hydrophobic regions in the N-terminus, and the consensus sequence FLXLXXXn, a putative neutral lipid-binding domain, exists in the first transmembrane domain. Finally, MGAT1 interacts with DGAT2, which serves to synergistically increase the TAG biosynthesis and LD expansion, leading to enhancement of lipid accumulation in the liver and fat.